Fix the bounds checking for returned zocalo results (#1004)

Co-authored-by: Dominic Oram <[email protected]>

src/dodal/devices/fast_grid_scan.py

@@ -45,8 +45,19 @@ def end(self):
         # refering to the first position
         return self.steps_to_motor_position(self.full_steps - 1)
 
-    def is_within(self, steps):
-        return 0 <= steps <= self.full_steps
+    def is_within(self, steps: float):
+        """
+        Determine whether a single axis coordinate is within the grid.
+        The coordinate is from a continuous coordinate space based on the
+        XRC grid where the origin corresponds to the centre of the first grid box.
+
+        Args:
+            steps: The coordinate to check
+
+        Returns:
+            True if the coordinate falls within the grid.
+        """
+        return -0.5 <= steps <= self.full_steps - 0.5
 
 
 class GridScanParamsCommon(AbstractExperimentWithBeamParams):

tests/devices/unit_tests/test_gridscan.py

@@ -1,4 +1,5 @@
 from asyncio import TimeoutError, wait_for
+from contextlib import nullcontext
 from dataclasses import dataclass
 
 import numpy as np
@@ -12,6 +13,7 @@
 
 from dodal.devices.fast_grid_scan import (
     FastGridScanCommon,
+    GridScanParamsCommon,
     PandAFastGridScan,
     PandAGridScanParams,
     ZebraFastGridScan,
@@ -246,63 +248,62 @@ def panda_grid_scan_params():
     )
 
 
-@pytest.mark.parametrize(
-    "grid_position",
-    [
-        (np.array([-1, 2, 4])),
-        (np.array([11, 2, 4])),
-        (np.array([1, 17, 4])),
-        (np.array([1, 5, 22])),
-    ],
-)
-def test_given_x_y_z_out_of_range_then_converting_to_motor_coords_raises(
-    zebra_grid_scan_params: ZebraGridScanParams,
-    panda_grid_scan_params: PandAGridScanParams,
-    grid_position,
-):
-    with pytest.raises(IndexError):
-        zebra_grid_scan_params.grid_position_to_motor_position(grid_position)
-    with pytest.raises(IndexError):
-        panda_grid_scan_params.grid_position_to_motor_position(grid_position)
-
-
-def test_given_x_y_z_of_origin_when_get_motor_positions_then_initial_positions_returned(
-    zebra_grid_scan_params: ZebraGridScanParams,
-    panda_grid_scan_params: PandAGridScanParams,
-):
-    motor_positions = [
-        zebra_grid_scan_params.grid_position_to_motor_position(np.array([0, 0, 0])),
-        panda_grid_scan_params.grid_position_to_motor_position(np.array([0, 0, 0])),
-    ]
-    assert [np.allclose(position, np.array([0, 1, 4])) for position in motor_positions]
+@pytest.fixture(params=["zebra_grid_scan_params", "panda_grid_scan_params"])
+def common_grid_scan_params(request):
+    return request.getfixturevalue(request.param)
 
 
 @pytest.mark.parametrize(
-    "grid_position, expected_x, expected_y, expected_z",
+    "grid_position, expected",
     [
-        (np.array([1, 1, 1]), 0.3, 1.2, 4.1),
-        (np.array([2, 11, 16]), 0.6, 3.2, 5.6),
-        (np.array([6, 5, 5]), 1.8, 2.0, 4.5),
+        [np.array([-1, 2, 4]), pytest.raises(IndexError)],
+        [np.array([11, 2, 4]), pytest.raises(IndexError)],
+        [np.array([1, 17, 4]), pytest.raises(IndexError)],
+        [np.array([1, 5, 22]), pytest.raises(IndexError)],
+        [np.array([0, 0, 0]), nullcontext(np.array([0, 1, 4]))],
+        [np.array([1, 1, 1]), nullcontext(np.array([0.3, 1.2, 4.1]))],
+        [np.array([2, 11, 16]), nullcontext(np.array([0.6, 3.2, 5.6]))],
+        [np.array([6, 5, 5]), nullcontext(np.array([1.8, 2.0, 4.5]))],
+        [np.array([-0.51, 5, 5]), pytest.raises(IndexError)],
+        [
+            np.array([-0.5, 5, 5]),
+            nullcontext(np.array([-0.5 * 0.3, 1 + 5 * 0.2, 4 + 5 * 0.1])),
+        ],
+        [np.array([5, -0.51, 5]), pytest.raises(IndexError)],
+        [
+            np.array([5, -0.5, 5]),
+            nullcontext(np.array([5 * 0.3, 1 - 0.5 * 0.2, 4 + 5 * 0.1])),
+        ],
+        [np.array([5, 5, -0.51]), pytest.raises(IndexError)],
+        [
+            np.array([5, 5, -0.5]),
+            nullcontext(np.array([5 * 0.3, 1 + 5 * 0.2, 4 - 0.5 * 0.1])),
+        ],
+        [np.array([9.51, 5, 5]), pytest.raises(IndexError)],
+        [
+            np.array([9.5, 5, 5]),
+            nullcontext(np.array([9.5 * 0.3, 1 + 5 * 0.2, 4 + 5 * 0.1])),
+        ],
+        [np.array([5, 14.51, 5]), pytest.raises(IndexError)],
+        [
+            np.array([5, 14.5, 5]),
+            nullcontext(np.array([5 * 0.3, 1 + 14.5 * 0.2, 4 + 5 * 0.1])),
+        ],
+        [np.array([5, 5, 19.51]), pytest.raises(IndexError)],
+        [
+            np.array([5, 5, 19.5]),
+            nullcontext(np.array([5 * 0.3, 1 + 5 * 0.2, 4 + 19.5 * 0.1])),
+        ],
     ],
 )
-def test_given_various_x_y_z_when_get_motor_positions_then_expected_positions_returned(
-    zebra_grid_scan_params: ZebraGridScanParams,
-    panda_grid_scan_params: PandAGridScanParams,
-    grid_position,
-    expected_x,
-    expected_y,
-    expected_z,
+def test_given_x_y_z_out_of_range_then_converting_to_motor_coords_raises(
+    common_grid_scan_params: GridScanParamsCommon, grid_position, expected
 ):
-    motor_positions = [
-        zebra_grid_scan_params.grid_position_to_motor_position(grid_position),
-        panda_grid_scan_params.grid_position_to_motor_position(grid_position),
-    ]
-    [
-        np.testing.assert_allclose(
-            position, np.array([expected_x, expected_y, expected_z])
+    with expected as expected_value:
+        motor_position = common_grid_scan_params.grid_position_to_motor_position(
+            grid_position
         )
-        for position in motor_positions
-    ]
+        assert np.allclose(motor_position, expected_value)
 
 
 @pytest.mark.parametrize(
@@ -333,11 +334,9 @@ def kickoff_and_complete(device: FastGridScanCommon):
 
 
 def test_given_x_y_z_steps_when_full_number_calculated_then_answer_is_as_expected(
-    zebra_grid_scan_params: ZebraGridScanParams,
-    panda_grid_scan_params: PandAGridScanParams,
+    common_grid_scan_params: GridScanParamsCommon,
 ):
-    assert zebra_grid_scan_params.get_num_images() == 350
-    assert panda_grid_scan_params.get_num_images() == 350
+    assert common_grid_scan_params.get_num_images() == 350
 
 
 @pytest.mark.parametrize(